Onyx<\/a> is a striated variety of chalcedony, a microcrystalline form of quartz. It is known for its parallel bands in contrasting colours, usually black and white. In the gem trade, the name is often used for black-coloured chalcedony, although true onyx is specifically defined by its layered structure. Onyx has been used for cameos, jewellery and decorative objects for centuries.<\/p>\n Major deposits of onyx include India, Brazil, Uruguay, the United States and Mexico. The mineral forms in cavities of volcanic rock, where silica solutions slowly crystallise into layers. Onyx chemically belongs to SiO\u2082 and has a hardness of 6.5 to 7 on the Mohs scale.<\/p>\n Sources: <\/strong> Onyx tumble stones from South Africa<\/p>","protected":false},"featured_media":62074,"template":"","meta":{"_acf_changed":false,"site-sidebar-layout":"default","site-content-layout":"","ast-site-content-layout":"default","site-content-style":"default","site-sidebar-style":"default","ast-global-header-display":"","ast-banner-title-visibility":"","ast-main-header-display":"","ast-hfb-above-header-display":"","ast-hfb-below-header-display":"","ast-hfb-mobile-header-display":"","site-post-title":"","ast-breadcrumbs-content":"","ast-featured-img":"","footer-sml-layout":"","theme-transparent-header-meta":"default","adv-header-id-meta":"","stick-header-meta":"default","header-above-stick-meta":"","header-main-stick-meta":"","header-below-stick-meta":"","astra-migrate-meta-layouts":"set","ast-page-background-enabled":"default","ast-page-background-meta":{"desktop":{"background-color":"var(--ast-global-color-4)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"ast-content-background-meta":{"desktop":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}}},"soort":[],"product_brand":[],"product_cat":[1044],"product_tag":[],"class_list":{"0":"post-62071","1":"product","2":"type-product","3":"status-publish","4":"has-post-thumbnail","6":"product_cat-trommelstenen","7":"pa_herkomst-zuid-afrika","8":"pa_maat-m-l-trommelstenen","9":"pa_soort-onyx","10":"pa_verkoopeenheid-per-100-gr","11":"pa_vorm-getrommeld","12":"desktop-align-center","13":"tablet-align-center","14":"mobile-align-center","15":"ast-product-gallery-layout-horizontal-slider","16":"ast-product-tabs-layout-horizontal","18":"first","19":"instock","20":"taxable","21":"shipping-taxable","22":"product-type-simple"},"acf":[],"_links":{"self":[{"href":"https:\/\/www.ruschmineralen.nl\/en\/wp-json\/wp\/v2\/product\/62071","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.ruschmineralen.nl\/en\/wp-json\/wp\/v2\/product"}],"about":[{"href":"https:\/\/www.ruschmineralen.nl\/en\/wp-json\/wp\/v2\/types\/product"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.ruschmineralen.nl\/en\/wp-json\/wp\/v2\/media\/62074"}],"wp:attachment":[{"href":"https:\/\/www.ruschmineralen.nl\/en\/wp-json\/wp\/v2\/media?parent=62071"}],"wp:term":[{"taxonomy":"soort","embeddable":true,"href":"https:\/\/www.ruschmineralen.nl\/en\/wp-json\/wp\/v2\/soort?post=62071"},{"taxonomy":"product_brand","embeddable":true,"href":"https:\/\/www.ruschmineralen.nl\/en\/wp-json\/wp\/v2\/product_brand?post=62071"},{"taxonomy":"product_cat","embeddable":true,"href":"https:\/\/www.ruschmineralen.nl\/en\/wp-json\/wp\/v2\/product_cat?post=62071"},{"taxonomy":"product_tag","embeddable":true,"href":"https:\/\/www.ruschmineralen.nl\/en\/wp-json\/wp\/v2\/product_tag?post=62071"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}
Mindat.org<\/a>, Gemdat.org<\/a>, Wikipedia - Onyx<\/a><\/small><\/p>","protected":false},"excerpt":{"rendered":"